The present invention relates to a ski boot, in particular for telemark skiing.
As is known, telemark skiing calls for boots with a flexible metatarsal region to permit turning with the heel raised off the ski, as opposed to clamped rigidly as in conventional skiing.
Telemark ski boots are traditionally made of leather to achieve the necessary degree of flexibility. In recent years, however, the trend has been towards plastic telemark ski boots, which are technically better, more attractive, stronger and more hardwearing than leather
To achieve the required degree of flexibility, the metatarsal region of plastic boots normally has a flexible-wall portion, the flexibility of which derives from it being made either to a particularxe2x80x94normally undulatedxe2x80x94shape or of more flexible material than the rest of the shell. The use of plastic materials with different mechanical characteristics for more or less flexible parts of the boot is made possible by co-injection processes.
Increasing the flexibility of one portion, however, may impair the torsional stiffness of the boot and, hence, ski control, performance and safety.
By way of a solution to the problem, EPO-A-1 023 849 proposes a boot shell with stiffening ribs extending along the lateral walls of the shell, between an intermediate portion of the sole, close to the flexible-wall portion, and a rear portion of the shell at the heel.
While improving torsional performance of the shell with respect to known boots, this solution has been found to still permit relatively severe torsional strain of the toe portion with respect to the rear portion of the shell.
Moreover, the flexible portion tends to be slow in a recovering its shape following deformation, and to retain a certain amount of permanent deformation after a given number of flexing cycles.
It is an object of the present invention to provide a plastic ski boot, in particular a telemark boot, designed to solve the aforementioned problems typically associated with known boots.
According to the present invention, there is provided a ski boot, in particular a telemark boot, having a shell made of plastic material and comprising a bottom wall, two lateral walls, a toe portion, a flexible portion extending crosswise with respect to the shell, close to said toe portion and at the metatarsus, and two longitudinal stiffening elements extending along respective said lateral walls of said shell from a rear portion of the shell, where they are joined, to said bottom wall and close to respective lateral ends of said flexible portion; characterized by comprising a stiffening frame built into said shell and integrally comprising said longitudinal elements, and a transverse structure connected to respective front ends of said longitudinal elements and extending close to said flexible portion so as to deform elastically alongside flexing of said shell.
Preferably, the transverse structure is annular and comprises a bottom portion embedded in the bottom wall, and a top portion extending crosswise with respect to the shell and substantially along a connecting portion between the flexible portion and the toe portion.